Several financial documents, bidding contracts and copied proprietary industrial processes were obtained by the hackers

McAfee Inc. announced that five multinational gas and oil companies and seven other unidentified companies have had their computer systems broken into by Chinese hackers, where sensitive information such as bidding plans have been stolen.

Dmitri Alperovitch, McAfee's vice president for threat research, named the attacks "Night Dragon" in McAfee's report.

"It speaks to quite a sad state of our critical infrastructure security," said Alperovitch. "These were not sophisticated attacks, yet they were very successful in achieving their goals."

The Night Dragon report did not release the names of the five energy firms, nor did it identify those responsible for the hacking. But the computer security company did report that the hack was traced to China through a server leasing company located in Shandong Province, which hosted the malware. It was also traced to Beijing IP addresses, which were being used between 9 a.m. and 5 p.m.

The report notes that the hackers infiltrated the computer systems either through public websites or infected e-mails sent to executives within the companies. They have obtained financial documents, bidding contracts and copied proprietary industrial processes.

"Starting in November 2009, coordinated covert and targeted cyberattacks have been conducted against global oil, energy and petrochemical companies," said McAfee in its report. "We have identified the tools, techniques and network activities used in these continuing attacks - which we have dubbed Night Dragon - as originating primarily in China."

The hackers not only broke into the computer systems, but also targeted executives and other individuals in Greece, Taiwan, Kazakhstan and the United States in order to obtain confidential information.

"That information is tremendously sensitive and would be worth a huge amount of money to competitors," said Alperovitch.

Alperovitch added that there is no evidence that the hack is "government sponsored in any way."

China has had quite a past linked to hacks like this, such as the hack on Google in December 2009. Chinese hackers broke into Google's network in an attempt to retrieve the e-mail accounts of Chinese human rights activists.

"This is normal business practice in China," said Jim Lewis, a cyber expert with the Center for Strategic and International Studies think tank. "It's not always state sponsored. And they do it to each other."

Foreign Ministry spokesman Ma Zhaoxu announced at a press briefing in Beijing today that he had no idea that the hack on the five energy companies had even occurred.

how the Great Firewall of China can be so effective at keeping their citizens from learning about Tiananmen Square, yet seems to act like a screen door when it comes to stopping cyber-terrorism originating from within their own borders.

exactly where do you cite the "great firewall's" effectiveness? To most internet users I've met in China, that firewall's nothing more than a nuisance. Just about everyone born in the '80s or later over there is familiar with using a proxy server.